title: Spatial structure of peptides determined by residual dipolar couplings analysis.
abstract: The gated decoupled (13)C NMR spectra of a dipeptide (Glu-Trp) and a tetrapeptide (NAc-Ser-Phe-Val-Gly-OMe) were recorded in D(2)O and in a lyotropic alignment medium (pentaethylene glycol monododecyl ether/n-hexanol). The residual dipolar couplings were extracted as the differences between the observed couplings for the magnetic nuclei dissolved in the latter and former media. Using a computational optimization, the spatial structures of the compounds were calculated starting from their respective low energy conformations obtained on a semiempirical basis. The uniformity of each conformation was confirmed by the solid-state (13)C NMR spectra of powder samples. Differences between the starting structures and final ones, optimized when employing residual dipolar couplings, are discussed.
authors.affiliation: Department of Physics, Kazan State University, Kazan, Russian Federation.
authors.forename: Vladimir V
authors.initials: VV
authors.lastname: Klochkov
authors.forename: Roustem F
authors.initials: RF
authors.lastname: Baikeev
authors.forename: Vladimir D
authors.initials: VD
authors.lastname: Skirda
authors.forename: Anton V
authors.initials: AV
authors.lastname: Klochkov
authors.forename: Farhat R
authors.initials: FR
authors.lastname: Muhamadiev
authors.forename: Igor
authors.initials: I
authors.lastname: Baskyr
authors.forename: Stefan
authors.initials: S
authors.lastname: Berger
mesh_terms: D002247:Carbon Isotopes; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry*
chemical_list: D002247:Carbon Isotopes; D010455:Peptides